/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package at.irian.web.jsf.orchestra;

import org.apache.myfaces.orchestra.conversation.ConversationManager;
import org.apache.myfaces.orchestra.frameworkAdapter.FrameworkAdapter;
import org.apache.myfaces.orchestra.requestParameterProvider.RequestParameterProviderManager;

import javax.faces.FacesException;
import javax.faces.context.FacesContext;

/**
 * @author Manfred Geiler
 * @author Gerhard Petracek
 */
class TransactionTokenRequestHandler
{
    private final static String REQUEST_PARAMETER_PROVIDER_INIT = TransactionTokenRequestHandler.class.getName();

    static void init(FacesContext facesContext) throws FacesException
    {
        if (isTransactionTokenEnabled(facesContext))
        {
            FrameworkAdapter frameworkAdapter = FrameworkAdapter.getCurrentInstance();
            if (frameworkAdapter == null)
            {
                throw new IllegalStateException("FrameworkAdapter not found");
            }
            if (frameworkAdapter.getSessionAttribute(REQUEST_PARAMETER_PROVIDER_INIT) == null)
            {
                // force reg. of ConversationRequestParameterProvider
                ConversationManager.getInstance();
                // initialize environmental systems
                RequestParameterProviderManager.getInstance().register(new TransactionTokenParameterProvider());

                // set marker
                FrameworkAdapter.getCurrentInstance().setSessionAttribute(REQUEST_PARAMETER_PROVIDER_INIT, Boolean.TRUE);
            }
        }
    }

    private static boolean isTransactionTokenEnabled(FacesContext facesContext)
    {
        return "true".equalsIgnoreCase(facesContext.getExternalContext().getInitParameter(WebXmlParameter.TRANSACTION_TOKEN_ENABLED));
    }
}
